Jiffy01

I'm new, obviously. Can someone explain the difference between s4 and s5, is there an advantage to one or the other? How do I identify what I have?

loudazzrx7

iTrader: (6)

You own a 86,so its a s4

'87 turbo II

iTrader: (1)

S4 has black rubber trim and molding on sides and bupmers and it has 4 sectiontaillights. The s4 N/a has 140 something horsepower and the S4 turbo has 182 hp.

S5 has body colored trim and front lip is more aerodynamic, badging is plastic rather than sticker and MAZDA logo on front bumper is raised. The N/A has 160 hp and the turbo has less lag and 200hp as well as tailights with round bulbs under smoked lenses. The easiest way t tell is body, taillights and year. if it's pre 89 it's S4 and S% for years 89 and later.

Fcdrift05

How much Horsepower did my car come with from the factory?
At the Flywheel ratings:
86-88 NA = 146 HP @ 6500 RPM w/ 138 Ft/lb @ 3500 RPM
86-88 Turbo = 182 @ 6500 RPM w/ 183 Ft/lb @ 3500 RPM
89-91 NA = 160 HP @ 7000 RPM w/ 140 Ft/lb @ 4000 RPM
89-91 Turbo = 200-202 @ 6500 RPM w/ 196 Ft/lb @ 3500 RPM
Infini IV = 215 @ 6500 RPM w/ 206 Ft/lb @ 3500 RPM

86-88 S4
89-91 S5

torean

hmm.....let me start....s5, being the newer version obviously have more power....146 to 160 for NA and 182 to 200 on the turbo....the s5 benefits from newer chassie/lower miles.higher compression rotors/better turbo...stock anti flood features, but suffers from electronic OMP....plastic tie rod ends..and worst of all.....those damn mouse belts...the s4 are better in terms of overall simplicity....rtek if u wanna get a turbo and is generally cheaper to pick one up

torean

damnit....3 ppl posted while i was responding...

Jiffy01

Thanks for the info. I thought it was mainly production dates, but wasn't really sure.

t-too

I have also been wondering about this while we're on the topic. Is there alot of differences between the wiring and ecu? Also, can you swap out the OMP from an s4? I'm thinking of s5in my s4 tII and most of the ones i find are with cut wiring harnesses so i'm trying to figure out how much of a pain it would be.

crashdummy

also since your new.... use the search function.

BklynRX7

If you wanted to swap the OMP you would also need the s4 front cover, i dotn see any reason why it wouldnt work. But hey, im no pro.

drunkclever

Any differnaces between the internals of the engines of the s4 and the s5?

Jager

iTrader: (10)

Some differences, the most noticable is the 9.4 (s4) to 9.7 (s5) compression ratios.

'87 turbo II

iTrader: (1)

and the turbos got an "independant twin scroll" which worked better than The TII S4s and din't use a valve. It made for less lag and 18 more horse power.

drunkclever

I am going to buy a s5 t2 engine.. what do I check for to make sure its a s5 t2.. the engine will be on a crate.

Sideways7

iTrader: (7)

I think one of the easiest things to look for is the EGR valve. s4 has it, s5 doesn't.

wiL87

I have a question. What S4 and S5 INTERIOR parts are not interchangable? I only need to know about the window switches but this can be for future reference.

Jager

iTrader: (10)

I guess I forgot to say I referring to NA's.

'87 turbo II

iTrader: (1)

that and S5 intercooler says "intercooled rotary turbo" where the S4s have "13b intercooled turbo II" notice S4 doesn't have the word "rotary" on it's intercooler at all. also S5s weren't called turbo IIs just turbos.

(hopefully Icemark or someone else knowelegable can come up behind me and clear it out, but the above info may only apply to S5s built 1990 and later) I'm not a 100% sure but that would be the non technical persons easy way of identification.

t-too

I'm not big on N/As, but isnt the intake manifold completely different on the s4 from the s5?

'87 turbo II

iTrader: (1)

yeah sorry I guess if I memorized the diff between turbo and N/A compression I would've known that. I was stating any "noticable differences" for any S4 to S5 engine

t-too

I thought that it was just the jdm motors that said that.

'87 turbo II

iTrader: (1)

well like I said I'm not sure, my only basis is VERY uneducated, it's just because my S4 says 13b intercooled Turbo II and I saw something that said Rotary intercooled turbo and it was sitting in an S5. So I assumed the difference.